Fuel pump control

ABSTRACT

An apparatus in a mechanical returnless fuel system is provided that includes a fuel pump motor for providing fuel to a powertrain system. A powertrain control module provides an activation signal for activating the fuel pump motor. A restraint control system includes a restraint control module for providing a disabling signal for disabling the fuel pump motor in response to a vehicle impact. An electronic relay switch is adapted for coupling to the fuel pump motor to selectably energize the fuel pump motor according to a conductive state and a non-conductive state of the electronic relay switch. A relay controller packaged with the electronic relay switch is responsive to the activation signal and the disabling signal for selecting the conductive state according to the activation signal when the disabling signal is not present and selecting the nonconductive state when the disabling signal is present.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTINGCOMPACT DISC APPENDIX

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates in general to a fuel delivery system, and more inparticular, to fuel pump control in a mechanical returnless fuel system.

2. Description of the Related Art

Inertia switches are commonly used in vehicles to disable the fuel pumpin the event of a severe vehicle crash. The inertia switch is similar toa relay that the inertia switch includes a first contact for receivingpower and a second contact for outputting power to the fuel pump motor.As opposed to an electric solenoid coil or some thermal expansion devicerequired to break the power feed circuit, the inertia switch uses amechanical element consisting of a steel ball in a funnel. The steelball is held in place by a magnet disposed in the bottom of the funnel.When the vehicle is subjected to impacts or vehicle roll, the steel ballwill break free from the magnet and roll up the funnel. At the top ofthe funnel is an arm switch mechanism. As the steel ball approaches thetop of the funnel, the steel ball contacts the arm switch mechanismthereby opening the circuit and disconnecting power to the fuel pump. Adisadvantage with the inertia switch is that proper calibration andpackaging of the inertia switch is becoming increasingly difficult dueto the characteristics of current vehicle structures.

The inertia switch is a stand-alone component that is separate fromcurrent production vehicle impact sensing systems which sense vehicleimpacts and provide safety countermeasures such as airbag deployment andother safety measures. It would be advantageous to replace the inertiaswitch without the expense if applying an additional system. Thereplacement unit for the inertia switch must also be reliable in sensingand determining a vehicle impact and also be compatible with the currentfuel delivery system such that it would not interfere with fuel deliverysystem in its normal operating state but only intervene in the event ofa vehicle impact.

What would be advantageous is to have a system that may be utilizedwithout changing the current architecture of the fuel delivery systembut have benefits of use with the vehicle impact sensing, notification,and fuel control operations.

BRIEF SUMMARY OF THE INVENTION

The present invention has the advantage of eliminating an inertia switchof a vehicle by utilizing the vehicle's restraint control module tosense a vehicle impact and provide a means via an electronic fuel pumprelay to disable the fuel pump. The received signal from the restraintcontrol module is preferably a frequency modulated signal which assistsin determining the validity of the received signal before deploying thefuel cut-off. The present invention includes the added benefit ofallowing the powertrain control module to variably control the fuel pumpin a mechanical returnless fuel system by using pulse width modulationvia the electronic fuel pump relay.

In one aspect of the present invention, an apparatus in a mechanicalreturnless fuel system is provided that includes a fuel pump motor forproviding fuel to a powertrain system. A powertrain control moduleprovides an activation signal for activating the fuel pump motor. Arestraint control system includes a restraint control module forproviding a disabling signal for disabling the fuel pump motor inresponse to a vehicle impact. An electronic relay switch is adapted forcoupling to the fuel pump motor to selectably energize the fuel pumpmotor according to a conductive state and a non-conductive state of theelectronic relay switch. A relay controller packaged with the electronicrelay switch is responsive to the activation signal from the powertraincontrol module and the disabling signal from the restraint controlmodule for selecting the conductive state according to the activationsignal when the disabling signal is not present and selecting thenonconductive state when the disabling signal is present.

Various objects and advantages of this invention will become apparent tothose skilled in the art from the following detailed description of thepreferred embodiment, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of a fuel pump control system according to thepresent invention.

FIG. 2 is a block diagram restraint control notification systemaccording to the present invention.

FIG. 3 a is a timing diagram of ignition battery voltage according tothe present invention.

FIG. 3 b is a timing diagram of deployment event notification accordingto the present invention.

FIG. 3 c is a timing diagram of fuel cut-off event notificationaccording to the present invention.

FIG. 3 d is a timing diagram of combined deployment event notificationand fuel cut-off event notification according to the present invention.

FIG. 4 is a logic table for the fuel pump control system according tothe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, there is illustrated in FIG. 1 a fuelpump control system, generally indicated at 10, according to the presentinvention. The fuel pump control system includes a smart fuel pump relay12 (i.e., electronic fuel pump relay) that is packaged in a relay module14 that may preferably provide the same vehicle connections as aconventional pump relay. The footprint of the smart fuel pump relay 12is similar to existing relay packages which allows the smart fuel pumprelay 12 to be plugged into existing junction boxes (not shown) andwhich makes it compatible with past and present powertrain and fuelsystem architectures. The smart fuel pump relay 12 is connected to apowertrain control module (PCM) 16 via a first communication line 17.The PCM 16 controls the operation of the powertrain system including afuel pump motor 18 which will be discussed in detail later.

The smart fuel pump relay 12 is connected to a restraint control module(RCM) 20 via a second communication line 21. The RCM 20 is incommunication with vehicle impact sensors (not shown) that sense vehicleimpact-related parameters such as acceleration, door cavity pressure,and rollover angular rate. Based on the received vehicle impact-relatedparameters, the RCM 20 determines an occurrence of a vehicle impact andprovides control signals to various deployable restraint devices such asharness restraint tensioners, deployable air bags, and window curtains.The RCM 20 also communicates an event notification signal (ENS) to thesmart fuel pump relay 12 in the event of a vehicle impact to disable thefuel pump motor 18 which results in fuel being cut-off from to the fueldelivery system.

The smart fuel pump relay 12 includes a relay controller 28 such as amicroprocessor or a logic driver circuit. An electronic relay switch 19is coupled in series between a power source 37, such as the ignitionsupply line, and the fuel pump motor 18. The electronic relay switch 19is operable for connecting power to and disconnecting power from thefuel pump motor 18 based on an output command received from the relaycontroller 28. The electronic relay switch 19 is in a conductive statewhen the contacts are closed and in non-conductive state when thecontacts are open. Preferably, the relay controller 28 is a solid statedevice and the electronic relay switch 19 includes mechanical contacts.Mechanical contacts provide longevity of the contacts for the electronicrelay switch 19. Alternatively, the entire smart fuel pump relay 28includes the electronic relay switch 19 may be a solid state device.

The smart fuel pump relay 12 further includes an over-current sensor 30,an over-voltage sensor 32, and an over-temperature sensor 34. Theover-current sensor 30, the over-voltage sensor 32, and theover-temperature sensor 34 monitor the current, voltage, andtemperature, respectively, of the solid state device itself.

The PCM 16 monitors and controls the operation of the powertrain systemincluding the fuel pump motor 18. The PCM 16 provides control signals tothe smart fuel pump relay 12 for controlling operation of the fuel pumpmotor 18 via the electronic relay switch 19. In addition to activatingthe fuel pump motor simultaneously with starting of the engine, anactivation signal from the PCM 16 may be used to control the speed ofthe fuel pump motor 18. The PCM 16 input behavior is based on anopen-drain type of interface in the PCM and a weak bias to high voltageon the PCM input of the smart fuel pump relay 12.

Controlling the operation of the fuel pump motor 18 via the smart fuelpump relay 12 is advantageous in mechanical returnless fuel systems(MRFS). Typically in a MRFS (not shown) a fuel pump motor is energizedby the maximum vehicle battery voltage for operating the fuel pump motorat a single speed in contrast to an electronic returnless fuel system(ERFS) which typically utilizes a computer or standalone module toelectrically control the duty cycle of the fuel pump motor to providethe precise amount of fuel as demanded. An advantage of the MRFS is thatthe MFRS is less costly than the EFRS. A disadvantage of the MRFS isthat the fuel pump constantly operates at 100% high speed which produceshigh current draw, reduces fuel efficiency, and generates heat build upin the fuel causing fuel vapor emissions.

Utilizing the smart fuel pump relay 12 in a MRFS allows the fuel pumpmotor 18 to be duty cycled without adding an additional controllingmodule since the smart fuel pump relay 12 is interchangeable withexisting fuel pump relay packages with a respective junction box. ThePCM 16 provides input commands (i.e., the activation signal) to therelay controller 28 for duty cycling the opening and closing thecontacts of the electronic relay switch 19 at timed intervals. Thisallows the fuel pump motor 18 to be controlled utilizing pulse widthmodulation (PWM). Preferably, the activation signal from the PCM 16includes a pulsed signal indicative of a respective duty cycle. Therelay controller 28 receives the activation signal and translates theactivation signal into a translated duty cycle for controlling the fuelpump motor (e.g., activation signal transmitted at 40% duty cycle andthe relay controller translates the duty cycle to 80% for controllingthe fuel pump motor at 80% duty cycle). Alternatively, the relaycontroller 28 may implement a duty cycle for the fuel pump motor 18equal to the duty cycle of the activation signal provided by the PCM 16.As another alternative, the PCM 16 may provide an alternatively encodedactivation signal to the relay controller 28 that is translated to arespective duty cycle for pulse width modulating the fuel pump motor 18at a respective duty cycle. Two or more operating speeds of the fuelpump using pulse width modulation may be activated by PCM 16.

The PCM 16 and the smart fuel pump relay 12 also allow for PWM undertunable conditions. For example, the tunable conditions may be based on(1) engine operation-based set points for switching between differentoperating speeds; (2) low power duty cycle; (3) combination of (1) and(2) above for maximum fuel economy; (4) time constants for speed ofswitching between operating modes; and (5) designed in hysteresis aboutthe switching set points.

As discussed earlier, the RCM 20 is utilized in cooperation with a smartfuel pump relay 12 under emergency vehicle impact conditions to disablethe fuel pump motor 18, but does not interfere with the operation of thefuel delivery operations during non-impact operating conditions. The RCM20 is hardwired via the second hardwired communication line 21 to thesmart fuel pump relay 12 and provides vehicle status informationdirectly to the smart fuel pump relay 12 in the form of the ENS. Whenthe power is provided to the vehicle after ignition key-on, the ENS isconstantly transmitted to the logic control circuit 28 of the smart fuelpump relay 12 throughout the key-on duration. The data within the ENScontains vehicle impact status information as to whether there is avehicle impact or whether there is no vehicle impact.

The smart fuel pump relay 12 receives and interprets the ENScommunicated from the RCM 20. The electronic relay switch 19 enters thenon-conductive state when the relay controller 28 determines that theENS contains a fuel cut-off request (i.e., disabling signal) made by theRCM 20. In the absence of the ENS containing a fuel cut-off request, theENS contains no-event status data which maintains the electronic relayswitch 19 in the conductive state and the fuel pump motor enabled at alltimes.

The PCM 16 also receives vehicle impact status information from the RCM20. Preferably, the communication is sent from the RCM 20 to the PCM 16by a dedicated third communication line 36. The impact statusinformation provides status information to the PCM 16 concerning theoccurrence of a vehicle impact and the request for fuel cut-off.Alternatively, the impact status information may be sent via a sharedbus line or wireless communication. In the event that a vehicle impactoccurs but communication from the RCM 20 to the smart fuel pump relay 20is not received (e.g., severed communication line), the PCM 16 maycommunicate a fuel cut-off request signal (i.e., disabling signal)directly to the smart fuel pump relay 12 as a back-up communicationsignal. The fuel cut-off request signal from the PCM 16 to the smartfuel pump relay 12 is in response to both RCM 20 directly informing thePCM 16 of the vehicle impact and the PCM 16 monitoring an ongoingpowertrain operation. That is, if the PCM 16 receives information that avehicle impact has occurred from the RCM 20 and the powertrain continuesto operate thereafter (e.g., operational for a predetermined period oftime), the PCM 16 may conclude that the communication from the RCM 20 tothe smart fuel pump relay 12 is not being received, and the PCM 16 willdirectly signal the smart fuel pump relay 12 to disable the fuel pumpmotor 18. After a vehicle impact has occurred and fuel pump motor 18 isdisabled, the PCM 16 may re-enable power to the fuel pump motor 18 aftera defined key-off key-on sequence or enablement event.

FIG. 2 illustrates a block diagram of the RCM's system architectureshown generally at 22. The RCM system architecture 22 includes aplurality of impact sensors 24 that are disposed at various locations ofthe vehicle. The RCM system architecture 22 further includes a least onemonitoring device 26 which provides occupant monitoring (e.g., occupantclassification), safety restraint monitoring for determining whether asafety restraint is enabled or disabled (e.g., seat belts), and seatposition monitoring for providing information regarding position of thevehicle occupant within a vehicle seat.

The plurality of impact sensors 24 and the at least one monitoringdevice 26 are connected to the RCM 20. In response to input datareceived from the plurality of impact sensors 24 and the at least onemonitoring device 26, the RCM 20 provides sensing operations such asimpact sensing, safing sensing, and rollover sensing. The RCM 20 furtherdetermines severity calculations, safety restraint deployment control,and safety restraint deployment notification. Impact event notificationsas determined by the RCM 20 may be communicated to the powertrainsystem, namely the PCM 16, to inform the PCM 16 of the fuel cut-offrequest or to other various subsystems 27 for either notification of theimpact event or to take corrective actions with respect to the impactevent. Other various subsystems 27 may telematics, security, andlighting systems.

The ENS transmitted from the RCM 20 to the smart fuel pump relay 12preferably comprises a frequency modulated signal. The frequencymodulated signal allows the smart fuel pump relay 12 receiving the ENSto distinguish between a disabling signal and potential noise on the ENSline which could otherwise be incorrectly interpreted as a request forfuel cut-off.

Referring to FIG. 3 a-d, there is shown signal characteristics of theENS. An ENS is provided on a single communication line having 3 logicstates that are output to each of the various control devices. The threelogic states include a normal state event, an airbag deployment stateevent, and a fuel cutoff state event. Each devices will receive all ofthe communicated logic state signals on the ENS, however, the variouscontrol devices will react only to a designated logic state with forwhich it is programmed to react to. Alternatively, two or morecommunication lines may be used to provide only the designated logicstate signal to its intended designated control device.

FIG. 3 a illustrates the battery voltage of the vehicle after theignition is switched to a key-on position for providing power to thevehicle including the powertrain system.

FIG. 3 b illustrates an ENS transmitted from the RCM (shown in FIG. 1)containing status data identifying an occurrence of a deployment event.A deployment event is defined as a time frame when a vehicle impact hasoccurred and decisions are made as to a severity of the vehicle impactand requests for safety countermeasures are communicated to thesubsystems as a result of the vehicle impact. Such countermeasures mayinclude airbag deployment, call to emergency services, and otheremergency options.

Upon a key-on operation and prior to a vehicle impact occurring, ano-event notification transmitted on the ENS line 50 is representativeof a normal operating state where there is no occurrence of a vehicleimpact and the vehicle is operating in its normal operating mode. Theno-event notification 50 is represented by a fixed frequency signal at10 Hz signal. The no-event notification is continuously transmitted bythe RCM to the smart fuel pump relay during the key-on ignition stateuntil the ignition is turned off or until a vehicle impact is sensed andnotification from the RCM to the smart fuel pump relay is required.

When a vehicle impact is detected, a time event-delay 52 is transmittedon the ENS line. The time event-delay 52 is a time delay where themodulating frequency of the ENS is zero for a predetermined period oftime (e.g., 4 ms to 10 ms). After the predetermined period of time haselapsed, a deployment event notification 54 is transmitted on the ENSline. The deployment event notification 54 is a fixed frequency signalat 250 Hz. The deployment event notification 54 begins on the risingedge of the 250 Hz cycle and is continuously transmitted at 250 Hz untilthe ENS transmission is complete or until a next notification eventrequires transmission such as a request to disable the fuel pump motor.

FIG. 3 c illustrates a fuel cut-off event notification, shown generallyat 56 on the ENS line. In the event the RCM (shown in FIG. 1) hasreceived input data that a vehicle impact has occurred and the RCMdetermines that fuel cut-off is required, the RCM interrupts thetransmission of the no-event notification 50 and transmits the timedelay-event 52 on the ENS line. After expiration of the time event-delay52, a fuel cut-off event notification 56 (i.e., disabling signal) istransmitted on the ENS line. The fuel cut-off event notification 56 isfrequency modulated for 5 cycles at 500 Hz followed by 5 cycles at 250Hz. This frequency modulation of 5 cycles at 500 Hz and 5 cycles at 250Hz is continuously repeated for the duration of the transmission of theENS or until a next event notification requires transmission on the ENSline. The initiation of the fuel cut-off event notification 56 begins ona rising edge of the first of the 5 cycles of the 500 Hz. In addition,there is no time delay-event between the alternating frequencies (i.e.,from 500 Hz to 250 Hz, and from 250 Hz to 500 Hz) within the fuelcut-off event notification 56. Since the fuel cut-off event notificationis typically a more severe impact event than the deployment eventnotification, it is desirable to have the fuel cut-off eventnotification clearly distinguishable from the deployment eventnotification. Added electrical noise coupled on to the ENS may causerespective control listening devices (i.e., controllers) to incorrectlyidentify a respective signal if the two signals were transmitted atdifferent fixed frequencies and were only distinguishable by a smalldifference between the fixed frequencies. Alternating the frequencies inthe fuel cut-off event notification provides added robustness fordistinguishing the fuel cut-off event notification from the deploymentevent notification and lessens the chances of an inadvertent fuelcut-off.

It should be noted that the relay controller of the smart fuel pumprelay is tunable so that only a partial handshake of the ENS may berequired to disable the fuel pump motor. For example, the relaycontroller may require that it see a minimum number of cycles (i.e.,number of cycles less than the 5 cycles at each respective frequency)for determining that request is made to disable the fuel pump motor. Theoccurrence of less than the transmitted number of cycles received by therelay controller may be the result of noise on the ENS; however,selecting a minimum number of cycles for determining the validity of thefuel cut-off request may still provide a reliable disabling signal fordetermining that a vehicle impact has occurred.

FIG. 3 d illustrates the fuel cut-off event notification 56 occurringafter the deployment event notification 54 has commenced on the ENSline. In the event the RCM (shown in FIG. 1) has determined that fuelcut-off is required during the transmission of the deployment eventnotification 54, the RCM interrupts the transmission of the deploymentevent notification 54 and transmits the time delay-event 52. Afterexpiration of the time event-delay 52, a fuel cut-off event notification56 (i.e., disabling signal) is transmitted. As stated earlier,transmission of the fuel cut-off event notification 56 shall begin onthe rising edge of the first of the 5 cycles at 500 Hz followed by 5cycles at 250 Hz. The fuel cut-off notification event 56 shall becontinuously transmitted until the ENS transmission is complete or anext event notification requires transmission on the ENS line.

FIG. 4 is a table illustrating the commands as received by the RCM andthe PCM and the resulting output of the smart fuel pump relay. As shownin the table, when a disabling signal is provided by the RCM which isindicative of a vehicle impact, the electronic relay is placed into thenon-conductive state by the relay controller thereby opening thecontacts of the electronic relay switch for disconnecting power to thefuel pump motor. The result is the cut-off of fuel to the fuel deliverysystem. Similarly, if a disabling signal is received from the PCM, thenthe electronic relay is placed into the non-conductive state by therelay controller and fuel pump operation is disabled.

Failure modes may also affect the decision making of the PCM. Forexample, if a low voltage is detected by the PCM, the contacts of thesmart fuel pump relay remain closed and fuel pump operation remainsenabled. If a short to ground fault occurs, then the contacts remainclosed and fuel pump operation remains enabled. In contrast, an opencircuit fault or a short to battery fault as detected by the PCM willdisable the fuel pump operation. When a RCM fault occurs, fuel deliveryremains enabled since it is undesirable to place the RCM in the criticalpath for basic vehicle operations. It should be noted the faultsillustrated in the table are exemplary and resulting operation of therelay switch and fuel pump operation may be modified as desired.

In accordance with the provisions of the patent statutes, the principleand mode of operation of this invention have been explained andillustrated in its preferred embodiment. However, it must be understoodthat this invention may be practiced otherwise than as specificallyexplained and illustrated without departing from its spirit or scope.

1. An apparatus in a mechanical returnless fuel system, said mechanicalreturnless fuel sytem including a fuel pump motor for providing fuel toa powertrain system, a powertrain control module for providing anactivation signal for activating said fuel pump motor, and a restraintcontrol system including a restraint control module for providing adisabling signal for disabling said fuel pump motor in response to avehicle impact, said apparatus comprising: an electronic relay switchpackaged outside of a fuel tank and adapted for coupling to said fuelpump motor to selectably energize said fuel pump motor according to aconductive state and a non-conductive state of said electronic relayswitch; a relay controller packaged with said electronic relay switchresponsive to said activation signal from said powertrain control moduleand said disabling signal from said restraint control module forselecting said conductive state according to said activation signal whensaid disabling signal is not present and selecting said nonconductivestate when said disabling signal is present.
 2. The fuel pump controlsystem of claim 1 wherein said restraint control module provides anenabling signal and said powertrain control module provides saidactivation signal to said relay controller for selecting said conductivestate.
 3. The fuel pump control system of claim 1 wherein said restraintcontrol module determines a fault in said restraint control system, andsaid conductive state is selected in response to said activation signalfrom said powertrain control module and said fault in said restraintcontrol system being present.
 4. The fuel pump control system of claim 1wherein said powertrain control module determines a low voltage in saidpowertrain system and said restraint control module determines a faultpresent in said restraint control system, and said conductive state isselected in response to said low voltage in said powertrain controlmodule and said fault in said restraint control system being present. 5.The fuel pump control system of claim 1 wherein said powertrain controlmodule determines a short to ground fault in said powertrain system andsaid restraint control module determines a fault present in saidrestraint control system, and said conductive state is selected inresponse to said short to ground fault in said powertrain control moduleand said fault in said restraint control system being present.
 6. Thefuel pump control system of claim 1 wherein said powertrain controlmodule determines an open circuit failure in said powertrain system, andsaid non-conductive state is selected in response to said open circuitfault signal from said powertrain control module being present.
 7. Thefuel pump control system of claim 1 wherein said powertrain controlmodule determines a short to battery fault in said powertrain system,and said non-conductive state is selected in response to said short tobattery fault from said powertrain control module being present.
 8. Thefuel pump control system of claim 1 wherein said restraint controlmodule is in communication with said powertrain communication module,said restraint control module providing disabling signal to saidpowertrain control module, said powertrain control module determining acontinuing operation of said fuel pump motor after receiving saiddisabling signal from said restraint control module, said powertraincontrol module providing said disabling signal to said relay controllerfor selecting said non-conductive state.
 9. The fuel pump control systemof claim 8 wherein said disabling signal is provided to said relaycontroller from said powertrain control module after said continuingoperation of said fuel pump relay for a predetermined period of time.10. The fuel pump control system of claim 1 wherein said disablingsignal comprises a frequency modulated signal.
 11. The fuel pump controlsystem of claim 10 wherein said disabling signal includes a firstpredetermined number of pulses at a first frequency followed by a secondpredetermined number of pulses at a second frequency.
 12. The fuel pumpcontrol system of claim 1 wherein said activation signal controls anoperating speed of said fuel pump motor.
 13. The fuel pump controlsystem of claim 12 wherein said operating speed of said motor iscontrolled by pulse width modulation.
 14. The fuel pump control systemof claim 1 wherein said relay controller includes is a microprocessorfor receiving input signals from the powertrain control module and therestraint control module.
 15. The fuel pump control system of claim 1wherein said relay controller includes is a logic driver circuit forreceiving input signals from the powertrain control module and therestraint control module.
 16. The fuel pump control system of claim 1wherein said electronic relay switch includes mechanical contacts. 17.The fuel pump control system of claim 1 wherein said electronic relayswitch includes a solid state device.
 18. The fuel pump control systemof claim 1 wherein said relay controller and said electronic relayswitch are integrally packaged as a conventional pump relay adapted tobe plugged into a vehicle junction relay box.
 19. A method forcontrolling a fuel pump motor of in a mechanical returnless fuel systemfor providing power to a powertrain system that includes a powertraincontrol module for providing an activation signal for activating a fuelpump motor and a restraint control module for providing a disablingsignal to an electronic fuel pump relay controller for disabling saidfuel pump motor in response to a vehicle impact, said fuel pump relaypackaged outside of a fuel tank including a relay controller thatoperatively controls a relay switch for energizing and de-energizingsaid fuel pump motor, said method comprising the steps of: sensing avehicle impact of said vehicle; communicating said disabling signal fromsaid restraint control module to said relay controller; determining avalidity of said disabling signal; and de-energizing said fuel pumpmotor via said relay switch in response to said disabling signal. 20.The method of claim 19 wherein further comprising the disabling signalis frequency modulated.
 21. The method of claim 20 wherein saiddisabling signal is frequency modulated at a first predetermined numberof pulses at a first frequency followed by a second predetermined numberof pulses at a second frequency.
 22. The method of claim 19 furthercomprising the step of: said restraint control module providing saiddisabling signal to said powertrain control module; determining acontinued operation of said fuel pump motor; and providing saiddisabling signal from said powertrain control module to said relaycontroller in response to said continued operation of said fuel pumpmotor.
 23. The method of claim 22 wherein said disabling signal isprovided from said powertrain control module to said relay controllerafter said continued operation of said fuel pump for a predeterminedperiod of time.
 24. The method of claim 19 further comprising the stepof controlling a speed of said fuel pump motor by said activationsignal.
 25. The method of claim 24 wherein said activation signal ispulse width modulated.
 26. The method of claim 25 wherein said relaycontroller modifies said duty cycle of said pulse width modulated signalfor controlling said speed of said fuel pump motor.
 27. The method ofclaim 24 wherein said activation signal is duty cycled for operatingsaid fuel pump motor in at least two operating speeds.